NAIROBI, Kenya (AP) ' The Pentagon's anti-IED unit says that bomb attacks in Nigeria, Kenya and Somalia became more frequent and deadly in 2011 as al-Qaida-affiliated terror groups used more sophisticated devices to kill more people with each explosion.

John Myrick, a U.S. military bomb expert, said militants introduced a deadlier type of bomb known as a shaped charge in both Somalia and Nigeria. Such deadly explosives were used by militants repeatedly in Iraq, and to a lesser extent in Afghanistan. The migration of the deadlier bombs to Africa is evidence that more sophisticated al-Qaida-linked groups are advising and training African militants.

Myrick said Nigeria saw a nearly fourfold jump in the number of improvised explosive device incidents last year, while Kenya saw an 86 percent increase.